It is known that if an intervertebral disc is damaged, it can be removed and the resulting space between the two adjacent vertebrae may be filled with a bone growth inducing substance to promote a honey fusion across the disc space. Fixation devices external to the disc space have been utilized to maintain the position of the adjacent vertebrae while the intervening material fuses with adjacent bone to form a honey bridge. As an alternative or in conjunction with fixation devices, load bearing spacers, such as artificial devices or bone grafts, may be placed in the empty disc space. These spacers transmit the loading from one adjacent vertebra to the other adjacent vertebra during the healing process. Such spacers may be provided in a variety of forms.
A need exists for improvements to existing interbody spacers and the present invention is directed to such need.